• If this is your first visit to the iboats.com Boating Forums, be sure to check out the FAQ. To post a question or comment, begin by signing up. To start viewing messages, select the forum that you want to visit from the selection below.
  • ALL iboats Forum Members and Guests:
    To show our appreciation for your participation in the Forums, we're offering an exclusive Forums-only discount good for an additional 5% off your iboats.com order for a limited time.
    To redeem, simply call our Customer Service Team at 800-914-1123 (Open M-F, 9am - 8pm Eastern Time) and mention the Forums 5% off discount. Offer excludes engines, trolling motors, and electronics.

Announcement

Announcement Module
Collapse

Help Tip: If you have a question that has not been answered to your satisfaction in the archives, it is always best to start a new thread of your own. By starting your own thread, you will receive the maximum number of views by forum members.

Below are some additional forum policies in hopes of all iboats members will follow, Thank you.

1. Please do not reply to old threads or hijack existing threads. Old threads of a technical nature are like a library book, Please do not write in them.

2. Old threads should be considered archives and used for reference only. Please do not reply to them.

3. Do not take over someone elseís thread (aka hijack) with your own question, even if it is similar. If you have a question that has not been covered to your satisfaction in the archives, it is always best to start a new thread of your own.

4. If you have a question for the original poster (OP) and the thread is over 30 days old, send the OP a PM, he may not even visit the forums any longer, or may not notice your question in the old thread.

5. By starting your own thread, you will receive the maximum number of views by forum helpers that may not even notice your question when itís posted at the end of someone elseís thread. And those answers will be specific to your particular issue.

6. Please do not post to threads that have been inactive for more than 3 months unless you are the original poster. We have very active forums and any thread that remains inactive for that long should be considered "dead". It is especially confusing when there is an entirely new question posted to an old thread.

7. Posting at the end of any thread is considered to be hijacking the original posters thread which in turn subjects the thread to be closed if it continues to happen thus not making it fair to the original poster in the future had for some reason he/she needed to return for additional information or provide an update of the problem solved which is always welcomed within a reasonable amount of time frame.

8. Please note that you should see a red banner pop up near the bottom of each inactive thread asking you not to reply to old threads. The Red banner will read: Please note this thread has been inactive for 90 days. For the best results, please start a new thread.

Thank you all in advance for doing your part in helping iboats run a smooth ship.

Additional forum rules linked below.
http://forums.iboats.com/forum-rules-guidelines-405/
See more
See less

How to pressure test an outdrive?

Page Title Module
Move Remove Collapse
X
Conversation Detail Module
Collapse
  • Filter
  • Time
  • Show
Clear All
new posts


  • How to pressure test an outdrive?

    About finished building my pressure tester. Seen a lot on the forums, but no procedure as to exactly what i'm looking for. I can't find it in the manual either...
    1) I assume just pump it up...to what PSI? for how long?
    2) Common leak points?
    3) Vacuum testing? yes or no? to what level?

    Thanks (I will NOT blow out another upper gear set this year
    '86 Glastron Conroy X-19, Merc 170
    '04 Carolina Skiff J14, 25 hp Mercury
    sigpic


  • #2
    Re: How to pressure test an outdrive?

    Originally posted by nola mike View Post
    About finished building my pressure tester. Seen a lot on the forums, but no procedure as to exactly what i'm looking for. I can't find it in the manual either...
    1) I assume just pump it up...to what PSI? for how long?
    2) Common leak points?
    3) Vacuum testing? yes or no? to what level?

    Thanks (I will NOT blow out another upper gear set this year
    If you go to about 10 psi you should be fine and use a spray bottle of soapy water to hi-light any leaks, bubbles will appear thats if you have a leaks at all
    'All other things being equal, a bigger engine makes more power.'
    1988 Bayliner 2150 Capri with 5.7 litre vortec engine and Cobra drive
    1979 Jem craft Southwind with 460 big block 550 Hp with Panther jet unit

    Comment



    • #3
      Re: How to pressure test an outdrive?

      Go to the ADULTS ONLY thread at the top of this forum. Then choose option 9 (Pressure testing an outdrive).

      Or, if you're really lazy, click HERE.

      Chris
      The world takes on a whole new perspective when viewed from 100' below...



      1972 Bertram 'Bahia Mar' 20
      2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
      **
      Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
      **
      Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

      Comment



      • #4
        Re: How to pressure test an outdrive?

        Originally posted by achris View Post
        Go to the ADULTS ONLY thread at the top of this forum. Then choose option 9 (Pressure testing an outdrive).

        Or, if you're really lazy, click HERE.

        Chris
        yeah, saw that before. more on building a tester than the actual testing. is there no procedure stating how long the drive should hold a particular pressure/vacuum?
        '86 Glastron Conroy X-19, Merc 170
        '04 Carolina Skiff J14, 25 hp Mercury
        sigpic

        Comment



        • #5
          Re: How to pressure test an outdrive?

          The manual for my Volvo outdrive is pretty specific about pressure and vacuum values and how long to hold each. Just need to convert metric to SAE if needed. Even the Seloc manual has the procedure.
          '76 Fiberform Custom 18
          Volvo AQ130D/280

          Comment



          • #6
            Re: How to pressure test an outdrive?

            Anyone know if its in the merc manual anywhere?
            '86 Glastron Conroy X-19, Merc 170
            '04 Carolina Skiff J14, 25 hp Mercury
            sigpic

            Comment



            • #7
              Re: How to pressure test an outdrive?

              mike,
              The good thing (and something embarassing thing) about this forum is the related links feature below a thread. Looks like Don S. mentioned the lack of presure & vacuum test info in the Merc manual. But it looks like there are some values and times for your Merc outdrive in the rest of the posts.

              Good luck.
              '76 Fiberform Custom 18
              Volvo AQ130D/280

              Comment



              • #8
                Re: How to pressure test an outdrive?

                Originally posted by nola mike View Post
                yeah, saw that before. more on building a tester than the actual testing. is there no procedure stating how long the drive should hold a particular pressure/vacuum?
                Most techs pressure test to about 10-12psi for 30 minutes... Vacuum test to about 10-12" for 30 minutes. You should see no losses in that time...

                The only thing I've found is that the shift shaft seal on the MC1 to A1 gear housings sometimes leak at about 6psi, if they are a bit old.

                Chris..........
                The world takes on a whole new perspective when viewed from 100' below...



                1972 Bertram 'Bahia Mar' 20
                2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
                **
                Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
                **
                Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

                Comment



                • #9
                  Re: How to pressure test an outdrive?

                  ok, so pressure test @ 10 psi loses maybe 1/2 psi (or a little less) in 45 min or so. spraying everywhere doesn't reveal a leak. vacuum testing, i hear a leak at the input shaft at anything over 5 mm hg. while i'm not thrilled with this, it appears that the input shaft seal isn't designed to hold a vacuum. also, i'm thinking this is less of a concern, since it isn't exposed to water anyhow...i'm tempted to at least give the drive a shot, and keep a close eye on the gear lube.
                  '86 Glastron Conroy X-19, Merc 170
                  '04 Carolina Skiff J14, 25 hp Mercury
                  sigpic

                  Comment



                  • #10
                    Re: How to pressure test an outdrive?

                    I test mine at 12 to 14 psi... Let it set overnight and no pressure loss.
                    The one manual i have states at least an hour.
                    So i guess there are so many different opinions on this...
                    sigpic

                    1981 ChrisCraft 210 Scorpion K,175 Johnson SeaHorse

                    Comment



                    • #11
                      Re: How to pressure test an outdrive?

                      Last year i just checked mine and drained a little and fill before i go out everytime .yeah the oil is 15.00 a qt. . i bought two and have some left for this year. Alot of people never check after the first time and never realize the have water or lost oil and burn it up. Go by 10 seal/washers and change them everytime you check. especially the bottom one. I hear it all the time that we lost our oil all at once and killed the drive but was never checked before they went out.
                      1973 Starcraft Supersport
                      120 mercruiser 153c.i.

                      Comment



                      • #12
                        Re: How to pressure test an outdrive?

                        Originally posted by nola mike View Post
                        ok, so pressure test @ 10 psi loses maybe 1/2 psi (or a little less) in 45 min or so. spraying everywhere doesn't reveal a leak. vacuum testing, i hear a leak at the input shaft at anything over 5 mm hg. while i'm not thrilled with this, it appears that the input shaft seal isn't designed to hold a vacuum. also, i'm thinking this is less of a concern, since it isn't exposed to water anyhow...i'm tempted to at least give the drive a shot, and keep a close eye on the gear lube.
                        Nola Mike,

                        I'd say you have a problem that needs finding. If it doesn't hold vacuum it WILL suck water in.

                        When you say 'input shaft' are you referring to the yoke at the front of the drive? If so, then that indicates the seal is faulty or the seal surface is grooved. It needs fixing!

                        Chris........
                        The world takes on a whole new perspective when viewed from 100' below...



                        1972 Bertram 'Bahia Mar' 20
                        2006 Mercruiser 4.3MPI (0W617679) w/Alpha 1 Gen II (0W829301)
                        **
                        Please don't send service questions in private messages. That's what the forum is for. Messages of thanks, always accepted.
                        **
                        Member of the month - April 2013. http://www.iboats.com/blog/achris-member-of-the-month/

                        Comment



                        • #13
                          Re: How to pressure test an outdrive?

                          Originally posted by achris View Post
                          Nola Mike,

                          I'd say you have a problem that needs finding. If it doesn't hold vacuum it WILL suck water in.

                          When you say 'input shaft' are you referring to the yoke at the front of the drive? If so, then that indicates the seal is faulty or the seal surface is grooved. It needs fixing!

                          Chris........
                          boo. yes, that's what i'm referring to. now, looking through the archives, it appears that this seal will leak at some low value when vacuum is applied. is that not the case? and where would the water come from (barring a bellows leak?) lastly, how hard is this to fix? is it a matter of removing the retaining ring and replacing a seal, or is it more difficult than that? hard to tell from the diagrams, and i haven't done that before...
                          '86 Glastron Conroy X-19, Merc 170
                          '04 Carolina Skiff J14, 25 hp Mercury
                          sigpic

                          Comment

                          Working...
                          X